History and Geography
Dengue has been known as a distinct disease entity for at least several centuries. Benjamin Rush is traditionally given credit for historical priority with his account of breakbone fever, the epidemic that afflicted Philadelphia in 1780.
Although his 1789 Account of the Bilious, Remitting Fever is generally accepted as the first modern medical account of dengue, claims have also been made on behalf of David Bylon, a Dutch physician who described an epidemic of knokkel-koorts (knuckle-fever), which appeared in the Dutch East Indies in 1779.The disease discussed by Bylon (1780) superficially resembles dengue (sudden onset of high fever, severe musculoskeletal pain, facial rash, and swelling, benign outcome), but appears atypical in that the severe joint pain suggested by the name is more characteristic of Chikungunya (CHIK) fever, a group A arbovirus infection with a mosquito vector. Bylon, state surgeon to the city of Batavia, treated 89 patients for knokkel-koorts and then caught it himself. His illness began with pain in the joints of his right hand and arm, and rapidly progressed to include a high fever within a few hours. He concluded his account of the epidemic by remarking that the disease was well known in Batavia, but had never before reached epidemic proportions. That alone would serve to distinguish knokkel-koorts from dengue, given what we know of the epidemiology of the latter disease.
Patrick Macdowall was a Scot who participated in the Darien Scheme, which was an attempt to found a Scottish colony in 1699 on the Isthmus of Panama, then known as Darien. The plan was the brainchild of William Paterson, the founder of the Bank of England, and was intended to gain for Scotland a share of the riches of the New World from Darien’s advantageous position astride the Atlantic and Pacific trade routes. The colonists were ravaged by disease, and Macdowall, who kept a journal still preserved in the National Library of Scotland, gave an excellent description of his own illness, which could well have been dengue.
Macdowall survived an acute febrile illness lasting 4 or 5 days that was characterized by nausea, vomiting, prostration, severe retro-orbital headache, disordered sensation of taste, bone and joint pain, generalized rash, and faintness. His convalescence was prolonged and marked by general weakness and a continual tendency to faintness.Was MacdowalFs illness dengue? Classical saddle-back fever occurs in only 50 percent of cases of dengue, and even Iymphadenopathy is not an invariable finding. MacdowalFs personal case history may well be the earliest recorded description of dengue.
The importance of the mosquito in the transmission of dengue was recognized early this century when T L. Bancroft, using human volunteers, proved that dengue could be transmitted via the bite of infected Stegomyia fasciata (A. aegypti) mosquitoes and that the infecting agent was neither an intracorpuscular parasite nor a bacterium, but an Ultramicroscopic organism. His observations also incriminated A. aegypti, of all the possible culprits, as the actual disease vector. However, he erroneously concluded that the dengue organism lives only for a few days in infected mosquitoes, because his attempts to transmit the disease were unsuccessful when he used mosquitoes that had been infected 15 or more days previously. The most likely reason for this error is the inadvertent inclusion of immune subjects in the study population. This, however, should not detract from the credit due him as the person who recognized the viral etiology and mosquito transmission of dengue long before Albert Sabin was able to cultivate the virus in the laboratory in the late 1940s.
Proof that A. albopictus is a vector of dengue came in 1931 when James S. Simmons and co-workers published an account of their experimental studies on dengue in the Philippines.
The general pattern of dengue activity since World War II has been one of increasing prevalence and severity within the context of unrestrained proliferation of its vectors. Today those vectors that spread yellow fever as well as dengue pose a very real threat to humanity.
James McSherry